The black friday deal at the box store might be a better offer
Only real difference I can see is the 720 is auto adjusting for thickness
Also appears that this unit includes added dust collection functionality and the ability to just press the clamp arm down to hold workpieces. The 520pro sounds like it would require the trigger to be depressed multiple times until tight, and also looks like the thickness presets are set for 1/2", 3/4", and 1 1/2". Not a big deal since most stock is going to be one of those anyway. Sounds like it’s just a function of whether it’s worth the extra 10 bucks to have quicker clamping/thickness setup and dust collection. Also, looks like the 520pro is $99 on the kreg website, so I don’t think that’s a black fiday offer, just the standard price.